Atlantic Sturgeon (Acipenser oxyrinchus)


The Atlantic sturgeon is a member of the Acipenseridae family of sturgeon. It has been used as a high-quality food fish and as a source of caviar since colonial days. It is anadromous, living much of its life in brackish or saltwater and spawning in freshwater rivers.

Dam construction, water pollution, and other changes in habitat, in addition to commercial overfishing, caused continued declines throughout the twentieth century. The Atlantic sturgeon is a threatened species today.

Other Names

sturgeon, common sturgeon, sea sturgeon, Albany beef; French: esturgeon noir d'Amerique.

Identification

The Atlantic sturgeon is dark brown or olive green with a white belly. The head is protractile and has a long flat snout with four barbels on the underside. Five rows of scutes (bony scalelike plates) extend along the length of the body; one is along the back, and two each are along the sides and the belly.

The centers of the scutes along the back and the sides are light, making them stand out in contrast to the darker surrounding color. These scutes are set extremely close together, and the bases of most overlap.

Size/Age

Atlantic sturgeon may live as long as 60 years and can attain a size of 14 feet. An 811-pounder is the largest known specimen. Fish exceeding 200 pounds are rare today.

Life history/Behavior

Spawning migrations last from late winter through early summer. Although it matures late in life, the Atlantic sturgeon is highly fecund, yet has a low reproduction rate, as females spawn only once every 3 to 5 years.

Females do not mature until ages 7 to 10 in their southernmost range and ages 22 to 28 in the northernmost range. Tagging studies have demonstrated that Atlantic sturgeon migrate extensively both north and south of their natal river systems.

Food and feeding habits

Juveniles and adults are bottom-feeding scavengers, consuming a variety of crustaceans, bivalves, and worm prey, as well as insect larvae and small fish.

Distribution

This species ranges along the northwestern and western Atlantic coast in North America from the Hamilton River in Labrador, Canada, to north-eastern Florida. It is currently more populous in the Hudson River, New York, than in other parts of its range, although it is not abundant there.

Habitat

The habitats of Atlantic sturgeon are primarily the estuaries and bays of large rivers, and deep pools of rivers when inland; in the ocean it inhabits shallow waters of the continental shelf.
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